Lots of sex is key to honeybee survival

Queen honeybees can have more than 100 different sexual partners, but that might not be enough for the survival of the colony.

There are very few situations where female royalty is encouraged to have multiple sexual partners. Okay, that probably never happens. But in the case of honeybees, it's key to their survival. At least that's what some researchers hope to prove.

Scientists from the University of Leeds are investigating possible causes of the widespread increase in honeybee deaths around the world. And they think they have the fix — lots and lots of sex, with multiple partners. By having a high number of diverse male partners, the queen honeybee could help protect her children from disease.

Honeybees have been hit hard here in the U.S. and in other areas like U.K. from things like colony collapse disorder (CCD). From 1972 to 2006, there was a dramatic reduction in the number of feral honeybees in the U.S. and a gradual decline in the number of colonies maintained by beekeepers. A 2007 survey across 13 states asked 384 beekeepers about the number of hives containing few or no bees in spring. About 23.8 percent met the specified criteria for CCD.

In 2008, U.S. average losses of honeybee colonies were 35 percent, where some beekeepers lost 90 percent of their colonies. One contributing factor might have been a virus, but that seems unlikely because the virus can be found in other countries — and those countries are not suffering the same losses.

While most attribute the problem to mites or insect disease, other possible causes have been noted. Some have suggested stress due to environmental changes or pesticides are taking their toll on the honeybees. Cell phone radiation and genetically modified crops have also been included as possibilities. Most likely, it is a combination of factors. The researchers say infections by hidden parasites in the genetically susceptible bees provide a "perfect storm" that could overwhelm the bees' defenses.

There is a big need to find out. From an environmental standpoint, as Einstein didn't say, "If the bee disappears from the surface of the Earth, man would have no more than four years to live." But the bottom line is that honeybees bring revenues of about $20 billion a year in the United States for pollinating services.

Dr. Bill Hughes from the faculty of Biological Sciences at the University of Leeds, says: “By making sure queens mate with enough genetically variable males, we may be able to boost resistance levels and so protect our honeybee populations from disease attacks like the ones we have seen hitting the U.S.”

They feel the reason some colonies are wiped out while others remain healthy is the genetic diversity of the hives. A dip in potential mates for the queen is becoming too low and therefore populations are less disease-resistant.

"An intriguing trait of honeybee species worldwide is that each honeybee queen mates with an extraordinarily high number of males," said Heather R. Mattila, a Cornell postdoctoral fellow in neurobiology and behavior and co-author of the article with Thomas D. Seeley, Cornell professor of neurobiology and behavior.

Queen honeybees will typically mate with up to 12 different male partners in a matter of minutes. Some will mate with up to 20 different males — and that isn't even a record. The queen bee of the ginormous Asian honeybee clan typically takes on 40 male partners, and was found to have mated with more than 100 different male partners.

The researchers will examine the genetic resistance of the honeybees by studying how they react to a common fungus parasite in a carefully controlled lab. The fungus is quite common in a majority of U.K. hives. It infects and "eats" the larvae, but it rarely kills a whole colony.